So I've only been riding with any regularity for about 3 years and while I can talk about PMs, and wheel selection like a pro I still have some relatively big gaps in basic bike know how.

Tonight I dropped a chain while riding outside. This is the second time I've dropped a chain since I got this bike in January, last time I managed to damage the chain (by catching it with the frame and then trying to pedal) as a bonus.

So, in this case I was close to cross chaining (I think going into an easier gear) so I shifted into the little ring at the same time I shifted the rear into a smaller ring. I find if I shift the front without adjusting the rear at the same time I get too big a jump and it throws off my pedal stroke.

Next thing I know I have zero power and my chain is dragging.

My question is "Is shifting both gears at the same time something I should avoid?". If not, then do I need to look at making an adjustment to my bike.

Last time I dropped the chain was different, I made the mistake of shifting gears while at a stop light, I was in too hard a gear to take off, and the vehicular traffic was heavy. Soon as I pushed down on the pedal it dropped.

So, dropping a chain as you change from the large to the small ring is caused my misaligned front derailleur. You can adjust for this, but sometimes when shifting under load you can still drop the chain. I hated this so I bought a chain catcher and it hasn't happened since! Best $20 I spent on my drivetrain.

If your dropping the chain off the small ring a small adjustment to the low limit screw in the front derailleur should take care of it. There are 2 screw on the FD. Generally they are marked, but it should be the inner most one. Shift into the small ring and turn the low limit screw clockwise a bit and hopefully that will take care of it.

When I shift I will ease up on the pedals a bit just for a split second especially when under a lot of power like hill climbing.

Don't shift when stopped. Anticipate the need to down shift when having to stop to set yourself to starting in the right gear.

If you drop your chain inside you can shift to big chainring and often pop chain back on without stopping. I don't drop my chain often but if I do most times I can get it back on with the shifting trick.

Why would you shift both front and rear derailuer at the same time? Do you run down or up your rear cassette and then change front derailuer as needed? In thinking about it, when I need to shift changing both front and rear, I do rear a split second before I do front, but I do easy off pedaling for maybe 1-2 pedal strokes.

I typically don't shift both at the same time. I will switch make my adjustment on the rear cassette first (usually up or down 2 gears) and then make my change on the front gear. It's been my experience that switching both gears at the same time leads to a fouled cadence anyway, not to mention the threat of a dropped chain which really throws off your cadence.

Sort of a thread hijack (sorry), but rather then start another noob chain drop thread...

I have a relatively new (less the 400 miles) bike with a carbon frame. Last night I dropped the chain, it stuck and when I went to restring it I realized that it had chipped away the finish and scratched up the carbon on the frame around the bottom bracket. Its not just a scratch is a full chain width and almost halfway around the crank. My question is does this damage the frame at all or is it purely cosmetic?

The frustrating part is that I just had it into the LBS to have the derailleur adjusted because I didn't want to play with it and an chance messing up my new bike and the tech specifically mentioned that he moved my chain guard in a bit because he thought it might be rubbing...Guess he moved it too far...

george-bob - 2013-05-15 12:00 AM So, dropping a chain as you change from the large to the small ring is caused my misaligned front derailleur. You can adjust for this, but sometimes when shifting under load you can still drop the chain. I hated this so I bought a chain catcher and it hasn't happened since! Best $20 I spent on my drivetrain.

Some bikes/drivetrains do seem more prone to dropping a chain. My speed concept is a prime example - chain catcher was the smartest decision I made. The dumbest was waiting so long to buy it.

To be clear the chain dropped off the rear toward the frame. Maybe it is just because I flipped the bike over to fix it but the chain was actually kind of caught between the frame and part of the gear assembly and it took me a few minutes to get it lose.

I will try shifting and pedaling next time it happens but if I get any resistance I'll stop.

To be clear the chain dropped off the rear toward the frame. Maybe it is just because I flipped the bike over to fix it but the chain was actually kind of caught between the frame and part of the gear assembly and it took me a few minutes to get it lose.

I will try shifting and pedaling next time it happens but if I get any resistance I'll stop.

You shouldn't be shifting front and back at the same time, and you shouldn't be shifting while stopped and not pedaling. If you only dropped your chain twice in 5 months due to these circumstances, I'm not sure you need to adjust anything. More likely user error.

Sort of a thread hijack (sorry), but rather then start another noob chain drop thread...

I have a relatively new (less the 400 miles) bike with a carbon frame. Last night I dropped the chain, it stuck and when I went to restring it I realized that it had chipped away the finish and scratched up the carbon on the frame around the bottom bracket. Its not just a scratch is a full chain width and almost halfway around the crank. My question is does this damage the frame at all or is it purely cosmetic?

The frustrating part is that I just had it into the LBS to have the derailleur adjusted because I didn't want to play with it and an chance messing up my new bike and the tech specifically mentioned that he moved my chain guard in a bit because he thought it might be rubbing...Guess he moved it too far...

Now that is a Bummer, seal the scratches with some nail polish, appropriate color if possible or clear if not to keep any moisture out and to make sure its sealed and no moisture can get into the carbon layer if it went that deep.

tri808 - 2013-05-15 2:30 PM You shouldn't be shifting front and back at the same time, and you shouldn't be shifting while stopped and not pedaling. If you only dropped your chain twice in 5 months due to these circumstances, I'm not sure you need to adjust anything. More likely user error.

The bolded was my main question. I knew better than to shift while stopped, I just got caught in traffic in the 2 miles between my house and the bike park I ride in and did something stupid.

User error is the most likely cause, although it sounds like a chain catcher might be in my future.

tri808 - 2013-05-15 2:30 PM You shouldn't be shifting front and back at the same time, and you shouldn't be shifting while stopped and not pedaling. If you only dropped your chain twice in 5 months due to these circumstances, I'm not sure you need to adjust anything. More likely user error.

The bolded was my main question. I knew better than to shift while stopped, I just got caught in traffic in the 2 miles between my house and the bike park I ride in and did something stupid.

User error is the most likely cause, although it sounds like a chain catcher might be in my future.

If you really need to shift the front chainrings while stopped, keep one foot clipped in and one foot on the ground. The foot that's clipped in should be in the position right before the downstroke...if it's not there, back pedal until it is. So about 10 o'clock for the left leg or 2 o'clock for the right. Now shift the FD, then lift the frame (I usually grab the back of the saddle) so the back wheel is off the ground and complete a full stroke. This should allow the chainring to shift smoothly and you're good to go once traffic resumes.

The biggest problem people have when shifting the front chainring when stopped is that we have a tendency to back pedal just a hair so we can get our lead foot in a power position. If you shift the FD, then back pedal even a quarter stroke, you'll probably drop your chain.

But also remember that when you drop you chain to the inside all you have to do is switch back to your big gear and it will come right back on. No need to stop.

Is this true? If so, I can't believe I haven't thought about it before. I've dropped my chain to the inside a couple of times and it really stressed me out.

100% true. I've done it many times. Especially on my Mtn Bik while flying down a hill.

Yup...just make sure to pedal slowly. All you're trying to do is get one tooth to catch the chain and it will work the rest of the chain back on. If you pedal too fast, the chain will just rattle against the teeth and it won't engage.